GMOs reduce chemical pesticide use, raise yields and boost farmer profits
Using GM technology produces a significant reduction in chemical pesticide use, a significant increase in crop yields, and a dramatic improvement in farmers’ profits
Source: PLOS ONE
On average, GM technology adoption has reduced chemical pesticide use by 37%, increased crop yields by 22%, and increased farmer profits by 68%.
Yield gains and pesticide reductions are larger for insect-resistant crops than for herbicide-tolerant crops, and improvements in both yield and profits are higher in developing countries than in developed countries..
These are among the conclusions of a meta-analysis of 147 original studies. Overall the authors confirm that – in spite of impact heterogeneity – the average agronomic and economic benefits of GM crops are large and significant. Impacts do vary though, especially by modified crop trait and geographic region.
Recent impact studies used better data and methods than earlier studies, but these improvements in study design did not reduce the estimates of GM crop advantages. Rather, NGO reports and other publications without scientific peer review seem to bias the impact estimates downward. But even with such biased estimates included, mean effects remain sizeable.
One limitation is that not all of the original studies included in this meta-analysis reported sample sizes and measures of variance. This is not untypical for analyses in the social sciences, especially when studies from the grey literature are also included. Future impact studies with primary data should follow more standardized reporting procedures.
Nevertheless, the findings reveal that there is robust evidence of GM crop benefits. Such evidence may help to gradually increase public trust in this promising technology.
Original paper: “A Meta-Analysis of the Impacts of Genetically Modified Crops” Wilhelm Klümper, Matin Qaim Department of Agricultural Economics and Rural Development, Georg-August-University of Goettingen, Goettingen, Germany published in PLOS ONE, Published: November 03, 2014. The full paper is available here.